1. Field of the Invention
The present invention relates to a device for use in skateboarding, skating activities and grinding. More specifically, the invention relates to an apparatus for facilitating the performance of tricks and stunts by skateboarders, skaters and grinders.
The sports of skateboarding, conventional roller-skating and inline skating have continued to increase in popularity since their inception decades ago. Each of these activities allows the participants the option of not only rolling on wheels that are mounted on the skate or skateboard but also the ability to slide across a raised surface such as the top of a common stair rail, edge of a street curb, back of a bus stop bench, etc. When sliding across these raised surfaces, it is common that the skateboard's or skate's wheels are not used as the point that is slid across the surface rather the area of either of these devices that is used is the bottom surface of the board or skate itself, or the components that hold the wheels in place commonly known as trucks. This activity is known as “Grinding” and continues to be a popular element in this category of sports.
2. Description of the Prior Art
Grinding, as previously described, has been so popular that specialized shoes have been developed for the grinding activity that have “Grind plates” mounted on the soles to facilitate grinding with the shoes themselves without the need to use a skateboard and skate of any kind. These shoes are similar to those disclosed in U.S. Pat. No. 5,970,631.
Recreational parks, which are specially equipped for these activities, are called “skate parks”. Skate parks offer a variety of challenging installations including grind surfaces for use by grinders, skateboarders and skaters. Unfortunately, these skate parks are costly to build and many communities and towns do not have the ability to provide them for use by the predominantly teenage and young adult population who would utilize them. For this reason, skate parks are usually few and far between. This requires the skateboarders, skaters and grinders to seek out other areas and obstacles to utilize for their sport. The areas and obstacles they usually find to utilize are public and private properties.
Unfortunately, not all skateboarders, skaters and grinders practice their sport in ways that are respectful of people or property. The general public, as well as local officials continue to complain and express concern about physical property damage in the form of scratched, marred and/or broken stair rails, benches and concrete surfaces as the result of being used for grind surfaces. Some business owners maintain that the presence of skateboarders, skaters and grinders in proximity to their places of business reduce their customer traffic and increase property owner's liability for the personal injury of the skateboarders, skaters or grinders and damage to their property.
The typical obstacles that are either provided at skate parks or found on public and private property are usually surrounded by concrete surfaces, which are unforgiving in the event that a skateboarder, skater or grinder falls against them or falls to the ground. Many rail obstacles particularly on private or public property are also at least 36″ above the surrounding surface they project up from, which increases the likelihood of serious injury if an individual falls from the top of them. Many of these rails are erected to prevent persons from falling from the surface they are standing on to a significantly lower surface in an attempt to limit injury from falling from one level to another. An individual who is grinding across the top of these types of rail installations risks serious injury and even death due to severe injuries if they fall from the top of the rail surface.
The activity of grinding in and of itself is harmless. Many teenagers are discouraged or forbidden to participate in grinding by their parents due to the problematic factors discussed here and mainly due to the severe risk of serious injury.
Many potential grind rail type surfaces are either the wrong profile, wrong material, not long enough or other wise not optimally suited for proper grinding and therefore don't offer the performer of the grinding activity a satisfactory experience. Potential grind surfaces that are desirable to utilize are often located in areas and positioned in such a way as to increase the likelihood of injury to the individual who is grinding as well as proximal, non-participating embers of the community.
There are existing materials that are commonly used in the fabrication of rails and tubular assemblies that may be used by consumers to create their own grind surfaces. Steel tube is the traditional material used in grind rail construction for skate parks and for stand-alone grind rails. Typical materials come in the form of lengths of metal tube of various profiles. These materials can be used to fabricate freestanding grind surfaces. The difficulty with this method is that the consumer must possess the ability and the machinery to fabricate, cut and weld metal components together. Even more specialized machinery is required to bend these metal profiles in arcs of differing lengths to change the trajectory of the grind surface to create the opportunity to perform additional stunts or tricks.
Many brands of steel grind rails exist and can be readily purchased. All of these use the commonly accepted round tube, box tube or u-channel steel that are bolted or welded to 2 or more stands of similar materials. These grind rails typically range from 6 to 10 feet in length. Most of these have straight grind surfaces, meaning that their grind surfaces follow one trajectory. Some have sections that angle upward or downward to facilitate performing differing tricks or stunts.
All of the grind rails with removable stands use welded on fixtures or fabricated boltholes on the bottom side of the grind rail to facilitate connection to the removable stands. This limits the ability to arrange the stands where they best serve the needs of the consumer.
All of the grind rails using steel components are typically very heavy and cumbersome to transport.
Any steel grind rail surface can become marred by contact with other metal surfaces that are slid across or impact it. The marring in the surface of steel can create a cutting or filing surface that rapidly wears the bottom or skateboards, skates and grind shoes or other athletic equipment. This rapid wear can severely lessen the usable life of these types of costly athletic equipment.
Some do-it yourselfers have built grind rails using plastic tube such as schedule 40 rigid PVC conduit tube material. This is a common commodity material in a form that is found at typical hardware and building supply retailers. PVC offers excellent grind characteristics. This plastic tube is not commonly used for the purpose of grinding since it is not as rigid as metal tube and requires fabrication of either a continuous support or numerous supports under it to solidify its structure to bear the weight of a human standing upon it. Currently, a device doesn't exist that provides an all in one, quick and easy way to attach the PVC tube to an underlying support that doesn't require hardware fasteners or chemical bonding.
Many play devices utilize small parts and hardware to affix individual components together into an assembly. Often times, the special tools that are needed to affix fasteners are not readily available. Numerous small parts are misplaced and not available to complete the final assembly of the device prior to utilization. A system that utilizes the fewest parts, hardware and use of tools for assembly has a competitive edge in the marketplace.
The following ten prior art patents and published patent applications are relevant to the field of the present invention:                1. U.S. Pat. No. 3,083,964 issued to Wentzel on Apr. 2, 1963 for “Amusement Device” (hereafter the “Wentzel Patent”);        2. U.S. Pat. No. 3,580,568 issued to Stone on May 25, 1971 for “Tightrope Device” (hereafter the “Stone Patent”);        3. U.S. Pat. No. 5,180,349 issued to Marcus on Jan. 19, 1993 for “Simulated Tightrope Walking Apparatus” (hereafter the “Marcus Patent”);        4. U.S. Pat. No. 5,718,412 issued to Levanas on Feb. 17, 1998 for “Portable Skating Rail” (hereafter the “Levanas Patent”);        5. United States Patent Application Publication No. U.S. 2002/0027224 A1 to Labelson on Mar. 7, 2002 for “Method And Apparatus For Converting Standard Lumber Into A Grinding Rail” (hereafter the “Labelson Patent”);        6. United States Patent Application Publication No. U.S. 2002/0050589 A1 issued to Nestel on May 2, 2002 for “Portable Grind Rail Assembly” (hereafter the “Nestel Patent”);        7. United States Patent No. U.S. Pat. No. 6,547,221 B1 issued to Bork on Apr. 15, 2003 for “Knock-Down Grind Rail For Skateboards And Rollerblades” (hereafter the “Bork Patent”);        8. United States Patent Application Publication No. U.S. 2003/0196308 A1 to Kelsey on Oct. 23, 2003 for “Grind Rail And Transport Kit” (hereafter the “Kelsey Patent”);        9. United States Patent No. U.S. Pat. No. 6,648,805 B1 issued to Millis on Nov. 18, 2003 for “Collapsible Grind Bar” (hereafter the “Millis Patent”);        10. PCT Application No. PCT/US97/23788 filed on Dec. 31, 1997 for “Traffic Cone Adapter Kit” (hereafter the “'23788 PCT Application”).        
The Wentzel Patent discloses an amusement device. There are sections of tubing which can either be rectangular or flat in cross section as illustrated in FIGS. 1 through 4 or alternatively, rounded in cross section as illustrated in FIGS. 5 through 8. The concept of this invention was to create a device for children to climb and walk along various narrow elongated objects. It is designed to simulate walking along fences, walls or curves.
The object of the invention is to provide an amusement or exercise device which can be stored and knocked down and then reassembled at the location for the children. As discussed in Column 2 beginning on Line 6, the triangular members can be made of any suitable material such as wood, metal or plastic. In the case of the embodiment as shown in FIGS. 5 and 6, the rails are supported by strap-like members as discussed in Column 2, lines 64 through 72, and Column 3, lines 1 and 2. There are also central struts 30 which provide interior support. This patent discloses the concept of having portable devices which can support along variations of separate support members an elongated tube member which can be either square or flat in top cross section or rounded in cross section for the purposes of enabling someone to walk on them.
The Stone Patent discloses a tightrope device which consists of a pair of separately supported block members 28 which support an elongated support member 4 which in turn has a grooved upper surface which supports a tightrope or rope 14 which is attached by various means such as adhesive or nails or other fasteners 18 as best illustrated in FIG. 3. The invention discloses the concept of having support members which support a tightrope so that one can walk on the tightrope.
The Marcus Patent also discloses a simulated tightrope. The simulated tightrope walking apparatus consists of a beam 10 which may be 10 to 12 ft in length and supported above a playing surface 12 such as an exercise mat or the ground on a pair of support members 14 and 16. The feel of a tightrope is simulated by a beam consisting of two elongated hollow tubes, preferably made of fiberglass for its tensile strength and flexibility, with one tube 26 loosely fitted within the other 24, as illustrated in FIG. 2.
The Levanas Patent discloses a portable skating rail. It is a modular series of square or tubular rails which are joined together by rigid or flexible connectors to provide a playing surface for in-line skates and skateboards. The rail section as illustrated in FIG. 5 can be circular and fit within a groove on a support block as also illustrated in FIG. 5. FIG. 8 shows a cross sectional view of a removably attached rail/column interface with a V-shaped support column. The rail be fixedly or removably attached to the support columns.
The Labelson Published patent application is a portable grinding rail assembly for use with skateboards, in-line skates, and the like. The assembly includes a beam that according to the inventor, is preferably made of stock wood, such as a two-by-four having support legs attached to each end of the beam. The assembly includes a cover or cap that sits on top of the beam and provides a riding surface for the skates. The cover and the support legs are removable from the beam so that the assembly is easily transported and to allow sale and shipment of the support legs and cover separately from the beam. The cover can also be L-shaped for use with existing, stationary supports, such as roadway curbs.
The Nestel Patent Application discloses a portable grind rail assembly. It includes a grind rail, two base portions, and two T-sections. each of the two base portions includes a planar ground-contacting surface for supporting the base portions above a ground surface. Each of the two T-sections is adapted for connecting one of the two base portions with the grind rail for supporting the grind rail above the ground surface. The grind rail is constructed of multiple rail sections that are adapted to be interconnected using a dowel.
The Bork Patent is a knock-down grind rail for skateboards and rollerblades. It is composed of at least two tubes held in alignment by tubular insert supports into opposing ends of the tubes. The tubes are clamped together end to end by a special, generally U-shaped clip having arms which are bent toward one another to form elbows. Supports are provided to support the tube above the ground.
The Kelsey Patent discloses a published patent application which is a grind rail and transport kit. It provides a portable and durable grind rail. To facilitate portability, the grind rail disassembles into rail pieces and stand pieces.
The Mills Patent is a collapsible grind bar. It is a collapsible rail glide or grind bard for use by skateboarders, in-line skaters and snowboarders. The device is collapsible and can be easily transported. As illustrated in FIGS. 7, 8, 9 and 10, the device essentially has a support structure which supports the grind rail above the ground so that an individual can grind the skateboard on it.
WIPO Patent WO 99/33526 is a traffic cone adapter kit. It is a system or kit for supporting cross bars on traffic cones using ring hanger 100 that fits onto the top of the cone and includes slots. A number of bracket slats can be hung from each slot. The brackets molded into the bracket slats hold the ends of the bars in shallow dished recessions, so that the bars are stable but are easily dislodged when kicked accidentally.
A need exists for a lightweight, portable, economical, relatively easily modifiable, easily assembled and disassembled grind rail system that can utilize the users choice of materials and can potentially extend the life of expensive skateboards, skates and grind shoes. Such a system would help accommodate the needs of grinders at all skill levels who need varying levels of difficulty and or varying levels of safety provided by underlying surfaces. Such a system would help lessen the use of existing public and private stair rails, curbs, benches and other potential grind surfaces. The consumer has their choice of tubular materials for this application. What is needed is a type of support that can be quickly and easily attached to tubes which provides the method of attachment without the need of tools and also provides a support structure to hold the tube above an underlying surface. Such a tube support would also make it possible for consumers to purchase inexpensive, readily available PVC tube materials, bend them into arcs to form new kinds of grind rail trajectories and support these with multiple easy to install supports that can be placed strategically along their custom formed rail in the placement of their choosing.